This 5.1 MHz circuit was found in a 1980s documentation. The frequency is given by the crystal and general purpose transistors can be used.
This circuit was found in a 90s American documentation. The circuit uses an LED that can be of a...
Damped sine oscillations can be produced when short pulses are applied to the input of this...
We found this circuit in the Philips integrated circuits manual of 1990. The circuit must be...